Coronary artery angiogram Computerenhanced coloured Xray angiogram of coronary blood vessels dark blue that feed the muscle of the heart The left coronary artery and its branches are seen here They follow the rounded shape of the heart orange In the background ribs green of the ribcage are visible An angiogram is made by injecting the blood vessels of the patient with an Xray opaque substance and then taking an Xray Blood vessels show up clearly allowing conditions such as coronary artery disease where the coronary artery narrows to be identified Blockages in the artery that lead to heart attack can also be identified